1. Field of Invention
The present invention relates to the technical field of microelectronics and solid state electronics, and specifically to a method for preparing an ultra-thin material on insulator through adsorption by a doped ultra-thin layer.
2. Description of Related Arts
In recent years, a silicon on insulator (SOI) material is capable of reducing, through a unique insulating buried layer structure thereof, a parasitic capacitance and a leakage current of a substrate, and is widely applied in various fields such as low-voltage, low-power-consumption, high-temperature, and radiation-resistant devices. SOI application technologies have been very mature in relevant fields, and strained silicon on insulator (sSOI) has also caught increasing attention of relevant technical personnel. Silicon germanium on insulator (SGOI) combines advantages of a silicon germanium material and the SOI, which can not only reduce a parasitic capacitance and a leakage current of a substrate, but also increase carriers' mobilities. The SGOI has also caught wide attention. To prepare a device having a smaller size and higher performance has always been an objective and an orientation in the development of the semiconductor industry, and with the very large scale integrated circuit technology achieving a level of a node of 22 nm and beyond, a higher requirement for a feature size of an integrated circuit is proposed. To further miniaturize a device based on a material on insulator, the thickness of the material on insulator is required to be thinner; therefore, an ultra-thin material on insulator emerges as the time requires.
Generally, a material on insulator is obtained by two procedures: material preparation and layer transfer, and the most common technology for implementing the layer transfer is bonding and ion-cut processes. However, in a conventional smart-cut method, a transfer layer is rather thick and the crack is large, a surface of a material on insulator obtained after ion-cut is rather rough, so it is difficult to prepare an ultra-thin material on insulator; moreover, because a rather high implantation dose is required, not only the production time and cost are increased, but also great damage is caused to the crystal, so it is more difficult to prepare a high-quality ultra-thin material on insulator.
Therefore, how to provide a method for preparing a high-quality ultra-thin material on insulator at low cost has already been a technical problem to be solved by practitioners in the art.